Mandocello conversion

[Verner]

As I work on completing my little outbuilding workshop, I am working on repair and setup projects. I am studying with a semi-retired repair person who is teaching me the ropes, geared towards building a business. I don’t have any hard plans to start up a business since I just gave one up, but if it organically grows into one that would be fine.

I found an old Kay and picked it up for $70, listed as parts. It obviously needed a neck reset and I wanted to try out my espresso machine setup. I am also having a local pro mandolinist sit in with my high school orchestra this year for a concert, so I thought it would be neat to put together a little mandolin orchestra of interested students for the performance, and we could play the Texas Fox Trot. I have three or four mandos at school I keep around for curious young musicians (as well as guitars, basses, even an accordion). Just need a mandola and a mandocello.

So while I have this thing apart I figured I would do a mandocello conversion. Figured it is a sort of bass in the mandolin family and some may be interested.

Keep in mind I am learning the trade, so some efforts will probably be clumsy as much of the work consists of first attempts.

So here she is!

 

[Verner]

Started by pulling the 15th fret and steaming the neck off. Someone in the past tried to repair it by forcing white glue in the back of the neck joint where it pulled up, as well as driving 3” decking screws into the heel. These old Kay’s are held together with hide glue, wood glue doesn’t stick to it very well. The joints can be pretty sloppy as well, since they were budget instruments in their day and I assume they were shimmed and sent out to simply be functional.

The steaming went fine, I got the white glue to a rubbery consistency and once the joint moved a bit I tapped the neck out. The decking screws did some damage, and the neck wood seems to be fairly soft, maybe poplar. It has a steel rod embedded, and seems straight still. I don’t know that it can handle the pull of 8 mandocello strings, so I may dive in there with some upgrades. We will cross that bridge later.

 

[Verner]

There were some rattling bits of kerfed lining in the body, and I noticed a crack in the neck block, so the top had to come off. It was open in a few spots anyway.

Using a seam separation knife, I ran it under the plywood top. I have done this with violins before. Old hide glue tends to crack and fracture, so this wasn’t bad at all. I didn’t need to use any heat, just worked slowly with even pressure. I did both sides until just the tail block was left. Then I worked that loose and wiggled it a bit until it popped off. Pretty clean separation. It gave me a good look at what I would be working with.

The neck block is cracked cleanly through on the bass side. This should come together with glue and a clamp or two.

The tail block is also split where the end pin is. Also a clean split on the grain, so it should glue up easily as well. I wouldn’t have caught that if I hadn’t popped the top. The lining should be an easy fix as well, will probably use hide glue there and titebond to replace the top. Needs some cleaning up as well, braces are overbuilt which is a good thing. The treble brace doesn’t have the best contact across the top so I may pop that and get the joint tighter. It hasn’t moved though, so maybe not. Hmm..

The top consists of three plies. No signs of delamination there. These were pressed in a form to achieve the arch. One nice thing about cheap instruments is they tend to be a bit overbuilt, both to move production along and to withstand abuse. Expensive acoustic instruments can be pretty fragile, but that’s where great tone lies.

 

[Verner]

It has the ‘T’ plate logo, which should mean it was made sometime between 1961 and 1965. Serial number is L5216 and the model is N-1.

 

[Bruce Johnson]

That looks like a cool project! And an interesting future for a poor battered up old Kay, that would probably otherwise be heading to the landfill. Giving trashed old musical instruments a new life is an honorable calling, and a fine retirement non-business.

Tell us more about mandocellos. Are they 8-strings, in pairs with octaves? Are they the same tuning as an 8-string bass, Ee Aa Dd Gg?

 

[Verner]

That looks like a cool project! And an interesting future for a poor battered up old Kay, that would probably otherwise be heading to the landfill. Giving trashed old musical instruments a new life is an honorable calling, and a fine retirement non-business.

Tell us more about mandocellos. Are they 8-strings, in pairs with octaves? Are they the same tuning as an 8-string bass, Ee Aa Dd Gg?

I would love to, instrument history is one of my favorite subjects!

Mandocello are pretty sweet instruments, and they almost died out. Pre jazz, the mandolin family of instruments were the most popular instruments out there. Mandolins are tuned like violins, and so a mandolin player had access to the huge library of violin music as well as mandolin-specific music. Companies like Gibson capitalized on the mandolin craze by branching the family out to include mandolin family equivalents of violas (mandolas), cellos (mandocellos), and even a giant mandobass. the guitar was considered part of the mandolin family at this point for Gibson.

Traveling music teachers employed by Gibson would start mandolin orchestras all over the country, endorsing the Gibson brand mandolin family instruments. They even used something called universal notation, so any player could play any mandolin family instrument but read the same music via transposition.

When jazz came about it relegated the mandolin to has-been status, and the revered Loar line of mandolins were an attempt to bring the mandolin back and not the mainstream, but the writing was on the wall. With the decline of the mandolin orchestra, interest in mandolas and mandocellos died out. The mandolin found new life in bluegrass and other trad genres.

Mandocellos are 8 string instruments, tuned like a cello. The lowest pair is tuned to a C, which is the same note as the A string 3rd fret on a bass. The other strings are tuned by pair in ascending 5ths, so low to high it is C, G, D, and A. It has a wide range and can cover melody and bass ranges. A Florentine style mandocello is a work of art. Gibson made that style as well as a simpler A style and guitar-bodied models, and lots of other companies made their own styles as well.

They are still fringe instruments today, but some well-known artists are starting to add them to their credentials. Enough that Eastman and a few other companies are producing nice instruments again.

 

[Bruce Johnson]

Thanks! Very interesting. I knew some about the mandolin orchestras and the mandobasses, but I wasn't sure how the mandocello fit in. Like a cello, duh!

I have a long background with American bluegrass music, and I've explored the history of the banjo orchestras, which have a similar historical path as the mando orchestras. Maybe you've seen my infamous Banjozilla?

But the cello range is very interesting to work in. A banjocello could be a useful instrument. And an electric bass-like instrument strung and tuned like a cello. Or an electric mandocello.

And your acoustic guitar-turned mandocello. I think it's a great concept.

 

[bassplace]

Very interested to see how this turns out. I have an Eastwood warren Ellis tenor baritone which is tuned like a mandocello but single strings. I would love an acoustic but have been looking for a guitar that has a skinnier nut. This conversion looks very promising.

 

[Verner]

Thanks! Very interesting. I knew some about the mandolin orchestras and the mandobasses, but I wasn't sure how the mandocello fit in. Like a cello, duh!

I have a long background with American bluegrass music, and I've explored the history of the banjo orchestras, which have a similar historical path as the mando orchestras. Maybe you've seen my infamous Banjozilla?

But the cello range is very interesting to work in. A banjocello could be a useful instrument. And an electric bass-like instrument strung and tuned like a cello. Or an electric mandocello.

And your acoustic guitar-turned mandocello. I think it's a great concept.

I have seen the banjozilla!! In fact, that may be the instrument that led me to this forum in the first place!

 

[Verner]

The first thing I do in the open body is clean up some of the gross old debris. It seems like someone dumped some liquid filler or something in the body. It accumulated at the tail block. I wonder if someone noticed the crack in the block and just tried to pour something in hoping it would solve the issue. Who knows.

I scraped all that gunk up and vacuumed it out. I am not going for spotless, just clean.

Then I tackled the head block. I use a brush and some water to ‘prime’ the crack. This is how Jerry Rosa does it on his repairs. I then use the brush to push glue into the crack, opening and closing the crack to use the capillary action to bring the glue everywhere.

When I have shoved way more glue than I need into the crack, I close it up with a clamp. I use another clamp to keep things aligned from the side so it doesn’t slide around.

I use rags, water, and q-tips to clean up the squeezout as best I can. I will let this set up overnight and take off the clamps tomorrow.

 

[Matt Liebenau]

Good stuff! Jerry’s a favorite of mine to.

 

[Verner]

Pulled the old school brass frets, or at least they look like old brass. They came out very easily, this is a dry fingerboard.

Looks like the radius is 9.5”.

but it doesn’t matter, because this fingerboard needs to come off. I want to make it a bit narrower at the nut to match Gibson specs, and between that and the increased tension of the paired strings I don’t think the steel reinforced neck will be up to the task. So off it goes.

Alternated between a hot iron on a wet rag and my seam knife. By that last pic I am sweating, it’s hard work!

 

[Verner]

!!!!!!!

LIAR!!!!!

There is no steel reinforcement in the neck!! Hahahahaha!!! No wonder it had a bow!

 

[Verner]

Oh man, I was in between just giving the fingerboard a new flat radius and refret, or taking the fingerboard off and installing a truss rod or carbon fiber rod.

Good thing I went this route.

 

[rudy4444]

Hi Verner, nice project! I'll follow along to see how it goes.

I used a Kay body to do a octave mandolin conversion which came out super. I broke the neck on my dad's Kay when I was something on the order of 13 or 14 years old, so I sawed it off at the body and then carried it around with me for the next 45 years. I had already built a F style mando and saw a Taylor GS Mini neck on Reverb for 50 bucks. I knew instantly the body was meant for this conversion using the Taylor 23-1/2" scale neck.

The body had painted "binding" that was worn away on several spots, so I carefully removed it down to the original finish. I added more support under the top where the neck would be positioned and cut a pocket to house the Taylor neck tenon. I used a long extension inserted in a hole drilled under the tailpiece end block to bolt the neck on.

You'll find some challenges to overcome, but this will be a great learning experience. Have fun!

 

[Bruce Johnson]

Hah! Yeah, that was a rare custom Lite model. Now you know what you have to do.

 

[rudy4444]

Oh man, I was in between just giving the fingerboard a new flat radius and refret, or taking the fingerboard off and installing a truss rod or carbon fiber rod.

Good thing I went this route.

Are you sure there's no bar under the filler strip? Kay buried the bar beneath the filler strip and added the board over the top in all the examples I've seen. (Use a strong magnet to check for the steel bar.)

I wouldn't be surprised it the board wasn't pulled off previously by someone. The dots and the frets look like they have been added. Many of these old Kays had pearwood fretboards, and they are truly "unfortunate looking" to quote Reese Witherspoon in "Legally Blonde" parlance.

The "T" logo is what some Kay aficionados refer to as the "Kelvinator Kays", since the logo looked so much like the refrigerator name plate.

 

[Verner]

Hi Verner, nice project! I'll follow along to see how it goes.

I used a Kay body to do a octave mandolin conversion which came out super. I broke the neck on my dad's Kay when I was something on the order of 13 or 14 years old, so I sawed it off at the body and then carried it around with me for the next 45 years. I had already built a F style mando and saw a Taylor GS Mini neck on Reverb for 50 bucks. I knew instantly the body was meant for this conversion using the Taylor 23-1/2" scale neck.

The body had painted "binding" that was worn away on several spots, so I carefully removed it down to the original finish. I added more support under the top where the neck would be positioned and cut a pocket to house the Taylor neck tenon. I used a long extension inserted in a hole drilled under the tailpiece end block to bolt the neck on.

You'll find some challenges to overcome, but this will be a great learning experience. Have fun!

View attachment 4432688

That looks great!!

 

[Verner]

Are you sure there's no bar under the filler strip? Kay buried the bar beneath the filler strip and added the board over the top in all the examples I've seen. (Use a strong magnet to check for the steel bar.)

No filler strip, it is just a routed channel with nothing in it!

 

[rudy4444]

No filler strip, it is just a routed channel with nothing in it!View attachment 4432693

Ah. I'd bet it has been removed in the past by somebody else.